Handle-locking means for fluid-pressure-operated tools



Nov. 24, 1925. 1,562,725

. a H. SHAFF HMIDIJ FOR FLUID PRESSURE OPIM'I' ID TOOL Filed larch 29, 1920 latented Nov. 24, 1925.

UNITED STATES PATENT OFFICE.

ERNEST H. SHAFF, OF GRAND HAVEN, MZCHIGAN, ASSTGNOR T0 WILLIAM H. KELLER, INC., 01? GRAND HAVEN, MICHIGAN, A COBJPORATION OF MICHIGAN.

HANDLE-LOCKING Iw'IEANS FOR FLUID-PRESSURE-OIPERATED TOOLS.

Application filed March 29, 1920. Serial No. 369,593.

To all whom it may concern.-

Be it known that 1, Banner H. SHAFF, a citizen of the United States, residing at Grand Haven, in the county of Qttawa and State of Michigan, have invented certain new and useful Improvements in Handle- Locking Means for Fluid-Pressure-Operated Tools, of which the following is a specification.

This invention relates to fiuid-p.ressureoperated tools of the type comprising a cylinder having a handle detachably secured on its rear end and closing one end of the piston chamben The general object of the invention is to provide means for locking the handle to the cylinder which is simpler, cheaper and more durable than means heretofore known for this purpose, and which is quickly and easily manipulated to lock and unlock the handle.

Another object of the invention is to provide a combined handle lock and exhaust deflector in which the functions of locking the handle and deflecting the exhaust current of motive fluid are performed by a minimum number of parts.

In the accompanying drawings, Figure 1 is a side elevational view illustrating a fluidpressure-operated tool embodying the features of my invention. Fig. 2 is frag mental side elevation partially in section, on an enlarged scale. Fig. 3 is a front end elevation with a part of the annular spring clip broken away to disclose the structure covered thereby. Fig. 4- is a detail view of the removable locking element.

In the drawings T have illustrated my invention as applied to a pneumatic hammer, and I will describe the construction in detail herein for the sake of imparting a clear understanding of the present embodiment of the invention, but it should be understood that I do not thereby intend to limit the invention to the present disclosure but aim to cover in the appended claims all modifications and equivalents falling within the scope of the invention.

Referring to the drawings, the exemplary tool shown comprises the usual cylinder 11 having in its front end a suitable working tool such as a rivet set (not shown) and a handle 12 having a tubular head 13 which surrounds and is screw-threaded upon the rear end of the cylinder 11.

Within the cylinder and the head 13 are the usual piston and valve mechanism which need not be herein described since my invention does not relate thereto. The exhaust ports through which the motive fluid escapes from the piston chamber to the atmosphere are indicated at 14, the outer ends of said ports opening upon an annular forwardly facing shoulder 15 on the cylinder 11 which shoulder is located in front of the forward edge of the handle head 13.

As hereinbefore stated, it is an aim of the present invention to provide a novel and improved means which serves the combined purpose of locking the handle head against rotation with relation to the cylinder and of deflecting the exhaust motive fluid issuing from the annular series of exhaust ports 14. The structure by which this object is accomplished will now be described.

The forward edge of the'handle head 13 is provided with a series of recesses or notches to form a series of teeth 16 extending entirely around the head. In the exterior of the cylinder 11 are formed a suitable number of grooves 17, in this instance four, running rearwardly from the shoulder 15 a suitable distance beyond the front edge of the handle head when in the rearmost position which it would ever occupy in use. A locking device 18 is shaped to complement the grooves 17 in the cylinder and the teeth 16 in the head so that when it is associated with both of these parts the cylinder and head will be prevented from rotation with respect to each other.

The locking device in the present instance is in the form of an arcuate plate having in its inner side a pair of ribs 19 which fit in the grooves 17, and having at its rear edge a series of notches forming teeth 20 which cooperate with the notches or teeth 16 in the head 13. The locking device is placed in operative position by entering the ribs 19 in the forward end of the grooves 17 and then sliding the device rearwardly to engage the head. Due to the curvature of the parts, the effect is the same as though the grooves 17 and ribs 19 were undercut or beveled so that the locking device cannot be Withdrawn radially from engagement with the cylinder but must be slid along the grooves 17 axially of the cylinder. If desired, a recess 21 may be formed in the outer face of the device to facilitate engagement of the device by the fingers or by a suitable tool.

An annular retaining clip 22 of proper strength and resiliency surrounds the locking parts described and has at its rear edge an inturned flange 23 to engage in an annular groove 24: in the outer face of the head 13, the forward portion of the ring being of smaller diameter to fit the cylinder in front of the shoulder 15. Between its ends, the ring is suitably formed to provide a continu ous annular shoulder 25 which abuts against the forward edge of the locking device 18 in any position of the parts so as to securely hold the locking device in its operative po- .sition.

Any suitable number of the grooves 17 may be provided but it is necessary only to employ a few. I have herein shown four such grooves spaced equidistant so that the locking device may be set in any pair of the grooves to have three different positions. The purpose of providing a plurality of positions for the locking device is to enable it to engage snugly with the toothed edge of the handle head in whatever position the head may occupy on the cylinder when turned up tight. The relative spacing of the ribs 19 and the teeth 16 is a differential one, so that the teeth of the locking device when in different positions will assume different relations to the teeth on the head. By providing for a plurality of positions of the locking device on the cylinder, the device may be mounted so that the two series of teeth will fully mesh with the square shoulders in abutment so as to form a rigid lock.

The space between the adjacent ends of the annular clip 22 when sprung apart to embrace the head 13, as seen in Fig. 1, forms the exit for the exhaust motive fluid issuing from the entire series of exhaust ports 14:. The clip 22 may be rotated about the head so as to position its exhaust space to discharge the current in any direction preferred by the workman.

I claim as my invention:

1. A pneumatic hammer having a cylinder, a handle screw-threaded onto the cylinder, said cylinder having a plurality of external longitudinally extending grooves and said handle having a plurality of teeth in one end thereof adjacent said grooves, a locking device comprising a key member adapted to interengage with one of said grooves and having teeth adapted to interengage with the teeth on the handle, said grooves and teeth being difi'erently spaced about the cylinder and handle respectively, the cylinder further having an exhaust port the outer end of which terminates adjacent said grooves, and an annular ring removably secured to the handle so as to be held against longitudinal movement relative thereto and having an inturned forward portion closely encircling the cylinder and forming an annular exhaust chamber into which said exhaust port is arranged to discharge, said ring further providing an annular shoulder adapted to engage with the forward end of said key member to hold it against forward movement in any one of said grooves.

2. A pneumatic hammer having a cylinder, a handle arranged to be screw-threaded onto the cylinder, said cylinder having a plurality of external longitudinally extending grooves and said handle having a plurality of teeth in one end thereof adjacent to said grooves, and a locking device comprising an arcuate plate having pair of ribs adapted to interengage with said grooves so as to be held against radial movement and teeth adapted to engage with the teeth on the handle, there being not less than three grooves in the cylinder and said grooves and the teeth on the handle being differentially spaced whereby said locking device is operable to hold the handle tightly screwed upon the cylinder.

3. A pneumatic hammer having a cylinder, a handle screw-threaded onto the cylinder, said cylinder having a plurality of external longitudinally extending grooves and said handle having a plurality of teeth in one end thereof adjacent said grooves, a locking device comprising an arcuate plate having a pair of spaced ribs adapted to interengagc with two of said grooves so as to be held thereby against radial movement and also having teeth adapted to interengage with the teeth on the handle, said grooves and teeth being differently spaced about the cylinder and handle respectively, the cylinder further having an exhaust port, the outer end of which terminates adjacent said grooves, and an annular ring removably secured to the handle so as to be held against longitudinal movement relative thereto and having inturned forward portions closely encircling the cylinder and forming an annular exhaust chamber into which said exhaust port is arranged to discharge, said ring further providing an annular shoulder adapted to engage with the forward end of said plate to hold it against forward movement.

In testimony whereof, I have hereunto set my hand.

ERNEST H. SHAFF. 

